Tag: leksah
I have a series of questions relating to debugging in Leksah, which does not seem to work, or maybe it is only me who is not using it correctly. I don't know.
I present the questions in a screencast because it is much more clearer to present it like that then in writing+pictures : https://www.youtube.com/watch?v=KeB8j_Viwrg
Main question : is this buggy behaviour of Leksah or is it only me who is not using it correctly ? If it is latter, how should I use the debug features correctly ?
Thanks heaps for making this video, it makes it much easier to follow what is going on!
I think the problem is that Haskell is really lazy. When you evaluated n at the very start of the debug session (before the video starts but you can see it in the log pane at the start of the video) n was replaced with the result (in this case 17). When you ask it to step into it there is nothing left to step into it is as iff you just had n=17 in the code.
Try restarting the the debug session or pressing Ctrl+B to force a :reload of the code. After you do this n should be an unevaluated thunk again and you should be able to step through it or set breakpoints in code it uses.
Generally Here's a editor/ide-agnostic solution to your problem: For language extensions, you can add this at the top of the source as a compiler pragma, which I prefer anyway: {-# LANGUAGE DeriveDataTypeable #-} instead of -XDeriveDataTypeable on the command line You can pass other command line options to GHC, like...
Check your indentation: maybe you're mixing tabs and spaces in a way that ghc interprets differently than leksah? I don't see another explanation for a parse error at print.
Thanks heaps for making this video, it makes it much easier to follow what is going on! I think the problem is that Haskell is really lazy. When you evaluated n at the very start of the debug session (before the video starts but you can see it in the...
I am afraid little has changed since the last time this came up. You can now make a GHCJS app and run it in the Out pane. It can include DOM input elements and handle DOM events. StdIn input is still unsupported.